title: Correlation of Aβ oligomer levels in matched cerebrospinal fluid and serum samples.
abstract: We recently reported a newly developed enzyme-linked immunosorbent assay (ELISA) for high molecular weight amyloid-β (Aβ) oligomers in which the same Aβ monoclonal antibody, BAN50, was used for both capture and detection in a single antibody sandwich enzyme linked immunosorbent assay (ELISA) system. Although our previous data have suggested that this assay will be useful for the early diagnosis of Alzheimer disease (AD) in cerebrospinal fluid (CSF) samples, the invasive CSF sampling procedure, with associated potential complications, limits use of these samples in routine clinical practice. In this study, we have demonstrated that our ELISA can detect signals in 60% of serum samples and in 80% of CSF samples obtained from non-demented subjects. Heterophilic antibodies that are reported to be a primary confounding factor in this type of ELISA system did not affect the signals obtained. Although the levels of serum Aβ oligomers were unexpectedly high, suggesting the possible detection of non-pathological Aβ complexes associated with serum carrier proteins, they did show a significant positive correlation with the levels obtained from matched CSF samples. This correlation between CSF and serum Aβ oligomer levels implies that the levels of serum Aβ oligomers measured with our ELISA might be useful as a marker for AD that reflects an intact system of Aβ transport across the blood brain barrier.
authors.affiliation: Department of Neurology, Kyoto Prefectural University of Medicine, Kyoto 602-0841, Japan. kasaita@koto.kpu-m.ac.jp
authors.forename: Takashi
authors.initials: T
authors.lastname: Kasai
authors.forename: Takahiko
authors.initials: T
authors.lastname: Tokuda
authors.forename: Mark
authors.initials: M
authors.lastname: Taylor
authors.forename: Masaki
authors.initials: M
authors.lastname: Kondo
authors.forename: David M A
authors.initials: DM
authors.lastname: Mann
authors.forename: Penelope G
authors.initials: PG
authors.lastname: Foulds
authors.forename: Masanori
authors.initials: M
authors.lastname: Nakagawa
authors.forename: David
authors.initials: D
authors.lastname: Allsop
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016229:Amyloid beta-Peptides / Q000032:analysis* / Q000097:blood / Q000134:cerebrospinal fluid; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D016229:Amyloid beta-Peptides
keywords: Amyloid-β; ELISA; Heterophilic antibody; Matched serum and CSF; Oligomer